In Earth science there is a paradox of the 100-kyr orbital eccentricity of the Earth about the Sun. The Greenland and Antarctic ice cores show that the 100-kyr cycle is the most dominent in driving the advance and retreat of the ice ages. But the solar radiation increase is universally excepted to be too small to be the direct driving force. Similarly the gravitational difference of around a 6% change in eccentricity is considered too small to influence the tides in a significant way. There is a possibility though that this tidal effect could be amplified if the Earth is considered to have a gravitational entropy gradient. By this I mean that the gravitational force experienced by matter increases towards the center of the Earth i.e. it is non-linear. This is not to be confused with a simple increase in density. It is the entropy of matter itself which I propose is reducing towards the center of the Earth. Has anyone ever thought of this before? I can't find any reports on this hypothesis. Can anyone help?